Means for connecting cord springs to attachment plug caps



Sept. 28, 1948. A. BELLIS I 2,450,369

MEANS FOR CONNECTING CORD RINGS TO ATTACHMEN U16 6 Filed lay 1947 Patented Sept. 28, 1948 MEANS Foa connsc'rmo corm Seamus T ATTACHMENT PLUG cars Alexander Bellls, Shelton, Conn.

Application May 1%, 1947, Serial No. 748,006

Claims. (Cl. 173-322) This invention relates a lead cord from electrical attachments connected with electrical connectors, such, for example, as attachment plug caps for plugging in the lead cords from electrical attachments in suitable outlets in a house wiring system, and has for an object to provide an improved means for securing such protecting means as coil springs embracing the insulated cord to the body of the plug or similar device.

Another object is to provide such a connection which may be employed with the male type of attachment plug caps or connectors.

With the foregoing and other objects in view, I have devised the construction illustrated in the the accompanying drawing forming a part of this specification. It is, however, to be understood the invention is not limited to the specific details of construction and arrangement shown, but may embody various changes and modifications within the scope of the invention.

In this drawing:

Fig. 1 is a longitudinal section of the cap and attaching means, but showing the cord and cord protector in elevation;

Fig. 2 is a-bottom view thereof with the spring and lead wires omitted; A

Fig. 3 is a top plan view of the outer member of a spring attaching means;

Fig. 4 is a side view thereof; v

Fig. 5 is a plan view of the insert member of the attaching means;

Fig. 6 is a side view thereof, and

Fig. 7 is a side view looking from the right of Fig. 6.

A very effective means of protecting the insulation of the insulated conductor cords leading to attachment connectors for electrical attachments, such as sadirons and the like, is a flexible coil spring embracing the insulated conductor cord as it passes through the opening in the body of the connector to the contacts carried by this body, and also extending a certain distance from this body, to protect the insulation of the cord from wearing or being frayed on the sides of the opening and also to prevent its being bent sharply at the entrance to the opening with danger oi. aftera while breaking the conductor wires as well as the insulation. It is often difficult, however, to properly connect this spring to the body of the connector. The present construction comprises a very simple and effective means for doing this with more effective protection of the insulated cord.

The construction i shown as applied to the to means for protecting I male type of attachment plug cap, as it has been more difflcult to properly connect the coil spring to this type of connector, but this construction is not limited to this specific device but is adapted for other types of connectors. As shown in the drawing, the attachment plug cap comprises a body member Ill of insulating material commonly molded of some suitable type of plastic material and providedwlth means for mounting the attachment plug blades Ii adapted for insertion in the usual entrance slots in a wall outletreceptacle or other outlet connector. These blades have feet l2 resting on shoulders l8 formed in the cap and secured by any suitable means, such as rivets it molded into the material of the cap and anchored therein, said feet also carrying the usual attaching means for the lead wires l5, such, for example, as the binding screws it. This body has a chamber or recess I! with an opening it; in the end wall leading to said chamber for passage of the insulated conductor cord l9 carrying the insulated conductor wires i5 leading to the blades ii and connected therewith by the binding screws IS in the usual manner. This cord is embraced by and enclosed within a flexible tubular protecting means, in this case comprising a flexible coil spring 20. Improved means is provided for connecting this spring to the insulating body III.

In forming this body, the opening I8 is made of somewhat smaller diameter than the width of the chamber or recess i'l' so as to provide an overhanging shoulder 21 at the inner end of the opening. The securing means for the spring protecting element 20 comprises an outer member 22, preferably in the form of a metal cupped member provided with an opening 23 in its bottom wall or closed end 29 and mounted and secured in thismember is an insert member 24, preferably in the form of a ring 25 with its opening 26 in alignment with the opening 23 in the cupped member 22, This member 22 forms a holder for the insert 24 and provides a stop shoulder at its free edge 22a to engage the outer surface of the body ill. At its opposite side edges the ring 25 is provided with legs 21 extending along the inner side walls of the cupped member 22 and 01' greater length than this cupped member so as to project from the open end thereof. In applying this device to the body ill these legs are passed through the opening I8 in the body until the free edge of the cupped member 22 rests on the outer surface of the body l0, as shown in Fig. i, and then the free ends of these legs are folded or bent over the shoulder 2|, as shown at 28 in Fig.

1. This securely fastens the securing device to the body In, the edge of the opening [8 being securely held or clamped between the lower edge of the cupped member 22, which forms a shoulder, and the bent over portions 28 of the legs 21. The insert 24 is secured in the cupped member 22 with the ring portion 25 seating against the inner side of the end wall 29 of this cupped member, and may be fastened by any suitable means, such, for example, as soldering or welding, or it could be a tight press fit in the cupped member. After this means is secured in position, a described, the protecting spring member 20 may be secured to it by threading it through the aligned openings in the cupped member and the insert, the coils of the spring separating sufiiciently to permit this action, as shown in Fig. l. The top wall 29 of the outer member, or the ring 25, or these two elements together, or either alone, thus form an inwardly extending annular flange or shoulder to engage between coils of the spring to secure it.

This coil spring is thus securely fastened to the body of this connector and will eiiectivel rotect the insulated conductor cord I9 passing through this spring coil to the interior of the connector for connection of the lead wires to the contacts carried by the connector.

It will be seen that in this arrangement the insulation of the cord is efiectively protected against wear or chafing by rubbing on the sides of the opening in the body member, and also is held against short bends over the edges of this opening, which might break the conductor wires or the insulation, but that the protector is fiexible so as to readily yield laterally by lateral strains on the cord. It will be apparent also that this improved securing means for the flexible cord protecting element is a very simple one involving only two parts. It can be easily and quickly applied to the bod of the connector, and when so applied will effectively and rigidly secure the protector 20 to this body; also that it will cover the entrance side to the opening in the body and provide a neat and attractive appearance.

Having thus set forth the nature of my invention, I claim:

1. A device of the character described comprising an attachment plug cap including a body member of molded insulating material having a chamber therein and an opening leading to the chamber of smaller diameter so that a shoulder is provided at the inner end of the opening, a coiled spring for embracing a conductor cord as the cord extends through said opening and means for securing the spring to the body member comprising a cupped member provided with an opening in its bottom wall, an insert in the cupped member comprising a ring at the inner side of said wall and legs extending from the ring along the inner sides of the side walls of the cupped member, said cupped member resting at its free edge against the body member with said legs extending through the opening and their free ends folded over the shoulder to secure it in place, and said spring extending through the opening in the cup and ring and held thereby.

2. An electrical attachment plug comprising an insulating body provided with a chamber and an opening of smaller diameter leading to the chamber so that a shoulder is formed at the in- I body and folded over the shoulder to secure the ner end of the opening. a cupped member resting at its free edge against the body and provided with an, opening in its bottom wall, an insert secured in the cupped member comprising legs extending through the opening in the cupped member thereto, and a coiled spring threaded into said opening in the cupped member and adapted to enclose a conductor cord leading to the chamber.

3. An electrical attachment plug comprising an insulating body provided with a chamber and an opening of smaller diameter leading to the chamber so that a shoulder is formed at the inner end of the opening, a coiled protector spring for embracing a conductor cord extending through said opening, and means securing said spring to the body member comprising a support provided with a shoulder engaging the outer surface of the body, legs extending from the support through the opening in the body and folded outwardl over said shoulder at their inner ends, and an inwardly extending flange in the nular flange at its outer end, an insert in said outer member comprising a ring at the' under side of said flange including legs extending through the opening in the body and folded over the said shoulder in the body member at their free ends, and said flange being seated between coils of the spring to secure it to the body member.

5. An electrical attachment plug comprising an insulating body provided with a chamber and an opening of smaller diameter leading to the chamber so that a shoulder is formed at the inner end of the opening, a cupped member resting at its free edge against the body and provided with an opening in its bottom wall, an insert secured in the cupped member comprising REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Name Date McArdle et al Dec. 1, 1931 Number 

